Unit 4- Yeasts

Question 1

Cryptococcus neoformans

Answer 1

Ulceration on mucous membranes, respiratory tract, meninges in CNS, and choroid in eyes

Question 2

Cryptococcus neoformans Disease

Answer 2

Systemic in cats, mastitis in cattle, endometritis and abortion in horse, other mammals and immune compromised humans

Question 3

C neoformans Characters

Answer 3

Spherical, monomorphic, sialic acids to degrade complement, phospholipase to disrupt host cell membranes, melanin antioxidant, thick capsule resists phagocytosis and stimulates T cells

Question 4

C. neoformans Growth

Answer 4

Warm room, chocolate agar, melanin pigment colonies, 4 antigen types, lives in dust and dirt

Question 5

C. neoformans Transmission

Answer 5

Respiratory, non contagious

Question 6

C neoformans Pathogenesis

Answer 6

Meningitis, encephalitis, CNS granuloma, bilateral miliary lesions in lungs, ulcerative papules in skin, nodule, granuloma, or ulcer

Question 7

C. neoformans Immunity

Answer 7

Antibodies to capsule, cell mediated, NK cells

Question 8

C. neoformans Diagnosis

Answer 8

India ink from exudates, tracheobronchial wash, CSF, wright and giemsa stain, blood agar culture

Question 9

Malassezia pachydermatitis

Answer 9

Oval budding yeast, green colonies on blood agar, aerobic or microaerophilic, 4 biotypes

Question 10

M. pachydermatitis Enzymes

Answer 10

Proteinase, chondroitin sulfatase, hyaluronidase, phospholipase

Question 11

M pachydermatitis Transmission

Answer 11

Ear and skin of mammals, opportunistic, associated with skin disease

Question 12

M. pachydermatitis Diagnosis

Answer 12

Wright giemsa smear, shoe print yeast, sabourad dextrose agar, PCR

Question 13

Candida albicans

Answer 13

Normal flora on mucous membranes of mammal and bird, immunocompromised susceptible, oval budding yeast with germ tubes that become septate mycelium, blastoconida, 2 serotypes

Question 14

Chlamydospore

Answer 14

Thick walled sphere on C. albicans mycelium in vitro

Question 15

Blastoconida

Answer 15

Blastospore, asexual spore produced by budding along hyphae

Question 16

C. albicans Enzymes

Answer 16

Adhesin, protease, neuraminidase

Question 17

C. albicans Transmission

Answer 17

Endogenous infection, hematogenous spread can lead to systemic infection

Question 18

C. albicans Pathogenesis

Answer 18

Adhesin, cell wall glycoprotein endotoxins, proteases, phospholipases, plaques with ulceration and inflammation in mucous surfaces, GI, mouth, stomach, genital, skin, claws, septicemia in respiratory and intestin

Question 19

C. albicans Disease

Answer 19

GI of birds, swine, and equine, pneumonia, enteric, mastitis, and systemic in cattle, ulceration on mucosa of dog and cat

Question 20

C. albicans Diagnosis

Answer 20

Blastoconidia, pseudohyphae, gram stain, wright giemsa stain, PAS, gomori methenamine silver